Generators of wind turbines must be aligned precisely in relation to the gearbox output shaft. This is carried out on the one hand during manufacture of the turbine and on the other hand after installation of the turbine and attachment of the rotor. Due to manufacturing tolerances and the forces acting on the wind turbine housing after rotor installation, it cannot be assumed that the generator can be installed so precisely in relation to the gearbox that the output shaft of the generator aligns precisely with the gear shaft. Generators therefore have to be brought into the correct position after mounting of the rotor.
This is usually carried out by lifting the generator by means of a crane, hoist, etc., and pushing it into the correct position. On the other hand, there are now devices which make the entire generator support movable. The alignment necessary is carried out horizontally and vertically in the direction perpendicular to the generator axis. Alignment axial to, i.e. in the direction of, the generator shaft is generally unnecessary, since misalignment in the shaft-hub connection can be compensated for.
An exclusively height-adjustable generator bearing is known, for example, from German utility model application DE 20 2005 001 519. This describes an elastomeric bearing, essentially consisting of a conical support or bearing foot, a conical elastomer bearing and a conical cap provided with the same cone angle, which has at the top a round threaded hole centrally along the vertical axis of the bearing, for the accommodation of the generator mount and is placed over the conical elastomer bearing, and has an adjustment device acting in the axial direction which enables the generator, which is attached to the central mount, to be adjusted in its position along the central axis of the bearing by raising or lowering.
Here the vertical adjustment can in practice only be carried out when the generator is not on the bearing, i.e. without load before installation and mounting of the generator. This is a significant disadvantage since, after the generator has been placed on the individual bearing elements, these are usually subjected to unequal loads, which can in turn result in misalignment. Any necessary readjustment is often only possible under more difficult conditions, e.g. by briefly relieving the load by lifting the generator block. In addition, horizontal adjustment of the generator cannot be carried out by means of the solution described in the utility model.
The objective was thus to provide a bearing which can be adjusted and accurately aligned in the vertical and horizontal position at any time, i.e. including after initial installation and initial mounting, in both directions under load, i.e. without removal or lifting of the generator block or machine block, in a simple manner and at any time, so that readjustments can also be carried out without problems if the conditions have changed due to operation (for example due to unequal fatigue of the bearing elements, etc.).
The object has been achieved by the provision of the bearing according to the invention, as described below and characterized in the claims.
The bearing according to the invention is suitable not only for generators for wind turbines, but also generally for heavy generators and machine parts which are connected to other components of the system or machine which are moving or subjected to movement.